Recently I faced some problem with Laravel schema builder: it does not support mysql set data type, which was necessary for one of my projects. After some searching for any information about it, I have found way to implement custom data types in schema builder. It a little bit ugly, but working well ;)

1. Extend 'Grammar' and 'Blueprint' classes

Put this code to the beginning of your migration file:

use Illuminate\Support\Fluent;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Grammars\MySqlGrammar;

/**
 * Extended version of MySqlGrammar with
 * support of 'set' data type
 */
class ExtendedMySqlGrammar extends MySqlGrammar {

    /**
     * Create the column definition for an 'set' type.
     *
     * @param  \Illuminate\Support\Fluent  $column
     * @return string
     */
    protected function typeSet(Fluent $column)
    {
        return "set('".implode("', '", $column->allowed)."')";
    }

}

/**
 * Extended version of Blueprint with
 * support of 'set' data type
 */
class ExtendedBlueprint extends Blueprint {

    /**
     * Create a new 'set' column on the table.
     *
     * @param  string  $column
     * @param  array   $allowed
     * @return \Illuminate\Support\Fluent
     */
    public function set($column, array $allowed)
    {
        return $this->addColumn('set', $column, compact('allowed'));
    }

} 

2. Replace default grammar and blueprint classes to ours

Insert this code before using Schema::create:

// register new grammar class
DB::connection()->setSchemaGrammar(new ExtendedMySqlGrammar());
$schema = DB::connection()->getSchemaBuilder();

// replace blueprint
$schema->blueprintResolver(function($table, $callback) {
    return new ExtendedBlueprint($table, $callback);
});

then replace Schema::create to $schema->create, like this:

$schema->create('example_table', function(ExtendedBlueprint $table)
{
    $table->increments('id');
    $table->text('sentence');

    // text source & author
    $table->string('author')->nullable();
    $table->string('source')->nullable();

    // technical data
    $table->set('difficulty', range(1, 10)); // use new datatype
    $table->boolean('enabled')->default(true);
});

Thats all, folks ;)

PS. Sorry for my English, I still studying it.